Regenerative air cycle refrigeration



Sept. 20, 1960 J. L. BARTLETT, JR 2,952,981

REGENERATIVE AIR CYCLE REFRIGERATION Filed May 25, 1959 INVENTORI JAMESL. BARTLETT, JR.

I A/forney.

United States Patent REGENERATIVE AIR CYCLE REFRIGERATION James L.Bartlett, Jr., Los Angeles, Calif., assignor to The Garrett Corporation,Los Angeles, Calif., a corporation of California Filed May 25, 1959,Ser. No. 815,425

'6 Claims. (Cl. 62-5) This invention relates to a regenerative air cyclerefrigeration system utilizing a vortex tube as one stage of the systemand employing as coolant for the hot tube of the vortex tube, theexhaust air from an enclosure being cooled.

In the operation of the system according to this invention, the heatedand pressurized air from the pressure source is first cooled in a heatexchanger in which the cooling air is passed therethrough by the actionof a fan or similar compression means driven by an expansion turbine.From the first heat exchanger, the compressed air is fed into a vortextube having a cold outlet from whence the compressed air passes into anexpansion turbine which drives the fan for the cooling air of the firstheat exchange stage. The cooled air exhausting from the expansionturbine is fed into an enclosure or chamber which is maintained also atan over-pressure which may be determined by the setting of an exhaustvalve. This still relatively cool air exhausting from the enclosure ispassed in heat exchange relation with the hot tube of the vortex tubeand thence to exhaust. It is contemplated that Within the scope of theinvention, gases other than air may be employed in the system and insuch case, the gas after performing its cooling function at the vortextube, will be fed to the entrance port of the compressor source, so thata closed system will result with no loss of the operating gas.

It is therefore an object of the invention to provide an expansioncooling system utilizing a vortex tube as a stage of the system in whichair or gas exhausting from a cooled enclosure is passed over the hottube portion of the vortex tube in heat exchange relation to eifectcooling of the hot gases therein.

Another object of the invention is to provide an expansion coolingsystem in accordance with the preceding object in which the heated andcompressed air fed to the vortex tube inlet is first cooled in a heatexchanger stage; and

It is a further object of the invention to provide an expansion coolingsystem in accordance with the preceding objects with the first heatexchanger stage cooled by a fluid whose flow is induced by a fan orother compressor driven by an expansion turbine forming a third stage ofthe system and fed from the cold outlet of the vortex tube.

Other objects and features of the invention will be readily apparent tothose skilled in the art from the specification and appended drawingillustrating certain preferred embodiments in which:

The figure represents the duct from the compressor source at 1 with thecompressed heated gas fed through heat exchange tubes 2 of a heatexchanger indicated generally at 3 and having a cooling duct 4 in whichthe tubes 2 are disposed and also having therein a fan 5 which inducesflow of ambient air or other fluid coolant through the cooling duct ofthe heat exchanger. The exit of the heat exchanger is connected by aduct 6 to the inlet chamber 7 of a vortex tube 8 having a hot tubeportion 9 provided with cooling fins 11. The vortex tube 8 has a coldoutlet 12 connected by duct 13 to an expansion turbine 14 which ismechanically coupled to drive the fan 5. The exhaust from the turbine 14is connected through a duct 15 to an enclosure 16 whose interior is tobe cooled and in which an over-pressure is to be established. Exhaustfrom the chamber 16 is passed through a duct 17 to a heat exchanger 18in which is disposed the hot tube portion 9 of the vortex tube 8. Flowof air or gas from the interior of the enclosure 16 through the duct 17is controlled by means of a regulating valve 19 which may be maderesponsive to either or both the pressure and temperature the chamber16, so as to eflFect the regulation thereof by varying the exhaust inaccordance with requirements and the quantity, temperature, and pressureof the air or gas fed into :the enclosure 16 through the duct 15.

It is thus seen that flow of exhaust air or gas from the enclosure 16will vary in quantity with the pressure and temperature of the airsupplied from the source compressor, while the quantity and temperatureof the air within the hot tube portion 9 of the vortex tube 8 willlikewise vary with the pressure and temperature of the source air, sothat the amount of cooling etfected in the heat exchanger 18 will thusvary with the heat load requirements. Thus, not only is utilization madeof the still cool exhaust air or gas from the chamber 16 to effect aregenerative heat exchange stage in the vortex tube, but also thiscoolant eflect automatically increases and decreases with increase anddecrease in the heat dissipation requirements of the hot tube portion 9of the vortex tube 8 so that the system operates with desirable economyand efliciency.

The terms air and gas have been used herein interchangeably and whenused in this specification and when used in the following claims, theterms are intended to be synonymous and to include not only air or gas,but also any combination of gases which it may be desirable to use inthe system.

While a preferred embodiment of the invention has been specificallydisclosed, it is understood that the invention is not limited thereto,as many variations will be readily apparent to those skilled in the artand the invention is to be given its broadest possible interpretationconsistent with the prior art.

What is claimed is:

1. An expansion cooling system for cooling an enclosure comprising asource of pressurized gas, a vortex tube for cooling said gas having aninlet, a hot tube and a cold outlet, means connecting said source to theinlet of said vortex tube, expansion means for further cooling said gas,means connecting the cold outlet of the vortex tube to the inlet of saidexpansion means, means connecting the outlet of said expansion means tosaid enclosure, an outlet for said enclosure, and means for passing thegas exhausting through said enclosure outlet ino heat exchange relationwith the hot tube of the vortex to e.

2. An expansion cooling system for cooling an enclosure comprising asource of pressurized gas, a vortex tube for cooling said gas having aninlet, a hot tube and a cold outlet, means connecting said source to theinlet of the vortex tube, an expansion turbine for further cooling saidgas, means loading said expansion turbine, means connecting the coldoutlet of said vortex tube to the inlet of the expansion turbine, meansconnecting the outlet of the expansion turbine to the enclosure, anoutlet for said enclosure, and means for passing the gas exhaustingthrough said enclosure outlet into heat exchange relation with the hottube of the vortex tube.

3. An expansion cooling system for cooling an en- Patented Sept. 20,1960- closurecomprising a source of pressurized gas, a first heatexchanger for lowering the temperature of said gas, means for inducingflow of coolant through said heat exchanger, a vortex tube having aninlet, a hot tube and a cold outlet, means connecting the outlet of saidheat exchanger to the inlet of the vortex tube, expansion means forfurther cooling said gas, means connecting the cold outlet of the vortextube to the inlet of the expansion means, means connecting the outlet ofthe expansion means to the enclosure, an outlet from said enclosure, andmeans for passing gas exhausting through said enclosure outlet into heatexchange relation with the hot tube of the vortex tube.

"f4. An expansion cooling system for cooling an enclosure comprising asource of pressurized gas, a first heat exchanger for lowering thetemperature of said gas, means for inducing flow of coolant through saidheat exchanger, a vortex tube having an inlet, a hot tube and a coldoutlet, means connecting the outlet of said heat exchanger to theinlet'of the vortex tube, expansion means for further cooling said gas,means connecting the exchanger, a vortextubehaving an inlet,-a hot tubeand sure therein, and means for passing the gas exhausting through saidoutlet valve into heat exchange relation with the hot tube of the vortextube.

'6. An expansion cooling system for cooling an enclosure comprising asource of pressurized gas, a first heat exchanger for lowering thetemperature of said gas, means for inducing flow of coolant through saidheat exchanger, a vortex tube having an inlet,a hot tube and a a coldoutlet, means connecting the outlet of said heat exchanger to the inletof the vortex tube, an expansion turbine driving said coolant flowinducing means, means connecting the cold outlet of said vortex tubetothe inlet of the expansion turbine, means connecting the outlet of theexpansion turbine to the enclosure, a regulating outlet valve for saidenclosure responsive to the value of'temperature therein, and means forpassing the gas exhausting through said outlet valve into heat exchangerelation with the hot tube of the vortex tube; v

References Cited in thefile of this patent UNITED STATES Y PATENTS

